You'll have the pictures on "good morning america." The battle against the flu tonight. What the cdc is now calling an epidemic the flu has spread to 47 states. And this evening, in some parts of the country, pharmacists with the vaccine are turning some patients away, saving it for the most vulnerable. Because so many people are coming in to get it. Here's abc's john schriffen. Reporter: Tonight, many around the country are desperately seeking for what seems like a golden ticket, the flu vaccine. Doctor's offices and pharmacies filled with patients. Hoping they're in luck. I was here yesterday and a gentleman came in and there was one left. He was a senior citizen, and I thought, shouldn't he have it more than me? Reporter: In new york the governor has declared a public health emergency. Is there enough to go around? My name is john schriffen. I'm calling from abc news. We reached out to a popular pharmacy chain here in new york city and got this response. Currently, we only have the flu shot for the elderly, the ones that are 65 and up. Reporter: That pharmacy's parent company, walgreens said select locations may experience shortages. But they're working quickly to restock every store. Cvs dealing with the same shortage issues. Today, we could possibly be getting 30 doses. But that could be gone in 20 minutes. Reporter: According to the essential fers for disease control, the flu has now spread to 47 states. If your local pharmacy is out of the flu vaccine head on over to flu.Gov. And it will tell you where to go. If you come into the pharmacy with flulike symptoms, doctors say, be careful not to double up on over-the-counter medications. David. John, good to keep in mind. I want to bring in dr. Jennifer ashton, you heard john report there, some pharmacists turning some patients away, saying 65 and older. That's going to make people nervous out there. Let's go through the numbers, david, there's still vaccine available. This year, there were 135 million doses made, about 128 million were shipped out or distributed. That's about 95% of the supply this year. Believe it or not, they started to work on next year's. I ran out in my office. I called and I got a shipment on thursday. Itt was a week ago, we were talking about children. Two more pediatric deaths. You also learned of a shortage of medicine for children. We're seeing a shortage in the antiviral vaccine tamiflu in its liquid form. And that's the form give on the children. Due to a shipping delay from the manufacturer. They're literally opening capsules and mixing it at the appropriate dose for children. But, again, we're waiting for those shipments to reach the pharmacies. Something that you told us in the newsroom today that struck me, how long members of family are contagious? Children are contagious longer than their parents. Absolutely. This is the thing about influenza. Adults and children can be contagious a day prior to beginning of symptoms. Children even longer than that. More than a week. If your kids are sick keep them home.

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